اثر افزودن یونجه خشک به عنوان جاذب ر طوبت بر کیفیت تخمیر و تولید پساب در سیلاژ ذرت

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانش‌آموختة کارشناسی‌ارشد، گروه علوم دام و طیور، پردیس ابوریحان، دانشگاه تهران، پاکدشت، ایران

2 دانشیار گروه علوم دام و طیور، پردیس ابوریحان، دانشگاه تهران، پاکدشت، ایران

3 استادیار گروه علوم دام و طیور، پردیس ابوریحان، دانشگاه تهران، پاکدشت، ایران

چکیده

هدف از انجام مطالعة حاضر، بررسی اثر یونجة خشک (به عنوان جاذب رطوبت) بر تولید پساب و کیفیت تخمیر سیلاژ ذرت بود. در طرحی کاملاً تصادفی در قالب فاکتوریل 4×3 به سه علوفة کامل ذرت با مادة خشک 3/18، 7/21 و 5/25 درصد، چهار سطح جاذب صفر، 5، 10 و 20 درصد اضافه و در سه تکرار در لوله‌هایی از جنس پلی‌وینیل کلریدی با عنوان سیلوی کوچک به مدت 90 روز سیلو شدند. با افزایش سطح استفاده از جاذب، مقادیر خاکستر و نیتروژن کل سیلاژها افزایش و الیاف نامحلول در شویندة خنثی به طور معنی‌داری کاهش یافت (05/0>P). اثر سطوح جاذب و رطوبت روی مادة خشک سیلاژها معنی‌دار بود و مادة خشک با 10 و 20 درصد جاذب بیشترین افزایش را نشان داد (05/0>P). تمام سیلاژها دارای pH مطلوب (در محدودة 79/3 تا 33/4) بودند. با وجود این، pH سیلاژها تحت تأثیر اثر متقابل رطوبت و سطح جاذب قرارگرفت (05/0>P). با افزایش سطح استفاده از جاذب، pH سیلاژها افزایش یافت اما این افزایش در سیلاژهایی با 26 درصد مادة خشک با شدت کمتری مشاهده شد. همچنین، مقادیر کربوهیدرات محلول باقی‌مانده تحت تأثیر اثر متقابل بین رطوبت و سطح جاذب قرارگرفت. بدین صورت که در سیلاژهای با 18 درصد مادة خشک اختلاف بین سطوح جاذب کمتر از اختلاف آنها در سیلاژهای با 22 و 26 درصد مادة خشک بود (05/0P<). با افزایش سطح یونجة خشک، پایداری هوازی در سیلاژهایی که رطوبت اولیة بالاتری داشتند بهبود یافت و به موازات افزایش مادة خشک اولیة علوفة ذرت، اختلاف در پایداری هوازی کمتر شد (05/0>P). با افزایش سطح یونجه در سیلاژ، تولید پساب کاهش یافت، به‌طوری‌که پساب در سیلاژهای حاوی 20 درصد یونجه خشک به صفر رسید (05/0>P). در پساب سیلاژهایی که سطوح بالاتری جاذب داشتند غلظت مادة خشک و نیتروژن بیشتر بود، اما کل مادة خشک و نیتروژن هدررفته در این تیمارها کاهش یافت. نتایج نشان داد استفاده از حداقل 10 درصد یونجة خشک باعث کاهش مؤثر پساب، بهبود پایداری هوازی و تولید ذرت سیلوشده با pH مطلوب می‌گردد.

کلیدواژه‌ها


عنوان مقاله [English]

Effects of addition of alfalfa hay as an absorbant on fermentation quality and effluent loss in corn silage

نویسندگان [English]

  • Somayeh Moeinizadeh 1
  • Ali Akbar Khadem 2
  • Ali Assadi-Alamouti 3
  • Ahmad Afzalzadeh 2
1 M.Sc. Student, Department of Animal and Poultry Sciences, College of Abouraihan, University of Tehran, Pakdasht, Iran
2 Associate Professor, Department of Animal and Poultry Sciences, College of Abouraihan, University of Tehran, Pakdasht, Iran
3 Assistant Professor, Department of Animal and Poultry Sciences, College of Abouraihan, University of Tehran, Pakdasht, Iran
چکیده [English]

The objectives were to investigate the effects of addition of alfalfa hay as an absorbent on fermentation
quality and effluent production of corn silage. Three levels of corn forage with dry matter (DM) contents
of 18.3, 21.7 and 25.5 percent were supplemented with 0, 5, 10, and 20 percent alfalfa hay, on as fed
basis, and ensiled in three replicates in polyvinyl chloride mini-silos in a completely randomized design.
Concentrations of ash and total nitrogen increased and that of neutral detergent fiber decreased
significantly as the level of absorbent increased (P< 0.05). Increasing the level of absorbent significantly
increased the DM of silage where the higher levels of DM were observed in silages with 10 and 20
percent absorbent. The pH values were within the optimum range of corn silage (ranging from 3.79 to
4.33); however, silage pH was affected by the interaction between DM and level of absorbent (P<0.05).
The pH increased as the level of absorbent increased, however, the effect was less observed in silages
with 26 percent DM. Also, there was an interaction between the DM and absorbent in the concentration of
residual water-soluble carbohydrate of silage where the differences in water-soluble carbohydrates in
silages with 18 percent initial DM were lower than those in silages with 22 and 26 percent DM. As the
level of absorbent increased, aerobic stability was improved with the effects becoming less pronounced as
the level of DM increased. Effluent production was markedly reduced as the level of absorbent increased
so that it dropped to 0 ml at 20 percent alfalfa hay addition at all DM levels (P<0.05). The concentrations
of DM and nitrogen were higher in effluent produced from silages treated with higher level of absorbent;
however, total DM and nitrogen losses were lower due to considerably lower effluent production. Results
showed that using a minimum of 10 percent alfalfa hay could effectively reduce effluent production and
improve aerobic stability of corn silage while maintaining its optimal pH.

کلیدواژه‌ها [English]

  • dry matter
  • ensiled forage
  • nutrient loss
  • silage effluent
Alli I, Thiffault C and Baker B (1985) A device for monitoring silage effluent produced in laboratory silos. Dairy Sceince. 68(12): 3355-3359.
Association of Official Analytical Chemists (1990) Official methods of analysis. 17th ed.  AOAC. Washington, DC.
Cummins B, O’Kiely P, Keane MG and Kenny DA (2007) Conservation characteristics of grass and dry sugar beet pulp co-ensiled after different degrees of mixing. Irish Journal of Agriculture and Food Research. 46(1): 181-193.
Dubois M, Giles KA, Hamilton JK, Rebes PA and Smith F (1956) Colorimetric method for determination of sugars and related substances. Analytical Chemistry. 28(4): 350-356.
Durmus O, Mustafa K, Adem K, Onder C and Cagri O (2006) Effects of ensiling alfalfa with whole-crop maize on the chemical composition and nutritive value of silage mixtures. Asian-Australasian Journal of Animal Science. 19(4): 526-532.
Ferris CP and Mayne CS (1994) The effects of incorporating sugar-beet pulp with herbage at ensiling on silage fermentation, effluent output and in-silo losses. Grass and Forage Science. 49(2): 216-228.
Fransen SC and Strubi FJ (1998) Relationships among absorbants on the reduction of grass silage effluent and silage quality. Dairy Science. 81(10): 2633-2644.
Graves RE and Vanderstappen PJ (1993) Environmental problems with silage effluent. Pages 291–299 in Silage production from seed to animal. Proceeding of National Silage Production Conference, Syracuse, NY. Northeast Region Agricultural Engineering Series, Cooperative Extention, Cornell University, Ithaca, NY.
Hameleers A, Leach KA, Offer NW and Roberts DJ (1999) The effects of incorporating sugar beet pulp with forage maize at ensiling on silage fermenrtation and effluent output using drum silos. Grass and forage Science. 54: 322-335
Harrison JH, Blauwiekel R and Stokes MR (1994) Fermentation and utilization of grass silage. Dairy Science. 77(10): 3209-3235.
Jasaitis DK, Wohlt JE and Evans JL (1987) Influence of feed ion content on buffering capacity of ruminant feedstuffs in vitro. Dairy Science. 70(7): 1391-1403.
Jones R and Jones DIH (1996) The effect of in-silo effluent absorbants on effluent production and silage quality. Agricultural Engineering Research. 64(3): 173-186.
Khorvash M, Colombatto D, Beauchemin KA, Ghorbani GR and Samei A (2005) Use of absorbant and inoculants to enhance the quality of corn silage. Canadian Journal of Animal Science. 86: 97-107.
Kung L (2010) Aerobic stability of silages. Proceeding of California alfalfa and forage symposium and corn/cereal silage conference. 14 pages. Visalia, CA, USA.
Licitra G, Hernandez TM and Van Soest PJ (1996) Standardization of procedures for nitrogen fractionation of ruminant feeds. Animal Feed Science Technology. 57(4): 347-358.
McDonald P, Henderson AR and Heron SJE (1991) The Biochemistry of Silage, 2nd ed. Holcombe Publications, UK.
Merriman RP (1988) Water pollution by silage effluent. Pages5–15 in B. A. Stark and J. M. Wilkinson, eds. Silage effluent.Chalcombe Publ., Marlow, UK.
Moran JP, Weinberg ZG, Ashbell G, Hen Y and Owen, TR (1966) A comparison of two methods for the evaluation of the aerobic stability of whole crop wheat silage. Proceeding of 6th International Silage conference. Aberystwyth, UK.
Muck RE and Holmes BJ (2000) Factors affecting bunker silo densities. Applied Engineering Agriculture. 16(6): 613-619.
National Research Council (2001) Nutrient Requirements of Dairy Cattle, 7th revised ed. National Academic Science,Washington, DC, USA.
Offer NWand Al-Rwidah MN (1989) The use of absorbant materials to control loss from grass silage: experiments with drum silos. Research Development. 6(1): 71-76.
Phipps, RH, Sutton JD, Beever DE and Jones AK (2000) The effect of crop maturity on the nutritional value of maize silage for lactating dairy cows. 3. Food intake and milk production. Animal Science. 71(2): 401-409
Ranjbari M, Ghorbani GR, Alikahni M, Khorvash M (2007) Chemical composition, crude protein fractionation and ruminal degradability of maize silage produced in Isfahan. Dairy Science. 2(1): 66-72.
SAS Institute (2002) User's guide (version 9), SAS Inc. Cary, NC, USA.
Staples CR (2003) Corn silage for dairy cows. Institute of Food and Agricultural Science. (IFAS). Document no. DS21. 7 pages. University of Florida.
Thomas PC and Robertson J (1987) Laboratory studies on the reduction of effluent losses from ensiled low dry matter crops. Proceeding of 8th Silage conference, Hurley, Maidenhead, UK.
Van Soest PJ Robertson JB and Lewis BA (1991) Methods for dietary fiber, neutral detergent fiber and non-starch polysaccharides in relation to animal nutrition. Dairy Science. 74(10): 3583-3597.
Woolford MK, Wilkinson JM and Cook JE (1983) Investigations on the effect of sodium bentonite and other moisture absorbants on the production of effluent from grass silage. Animal Feed Science and Technology. 8(1): 107-118.